I agree about precancel, only.
The good news is that Yvert says it is only found with one of their two precancel types (
surcharge rotative), so you don't need a second hole to fill...
The bad news is (there's always bad news, no?), Yvert splits this out into the precancel set, and there are four other major numbers in the set (3c, 4c, 5c and 10c) for this design (plus varieties).

Pretty page.